Work with the interferon inducer poly ICLC was extended in several directions. With one low level dose, it is effective against street rabies in monkeys. Phase 1 studies in man to determine what level of drug is toxic have been completed. 10 to the 4th power units of interferon/ml of human serum have been produced, possibly the highest serum interferon level man has ever experienced. At this level a marked drop in platelets was seen. Lower levles of drug did not produce this drop. The drug's effectiveness as an immune adjuvant has been observed with three vaccines, Venezuelan equine encephalitis virus, Swine flu virus, and H. influenzae. Relationships between the interferon system and protection against damage by X-irradiation have been explored. BIBLIOGRAPHIC REFERENCES: Green, J.A., Williams, J., and Levy, H.B.: Specific restoration of delayed hypersensitivity by lymphoid tissues extracts. J. Immunology 118: 1936-1943, 1977. Levy, H.B.: Studies with a stabilized derivative of poly I. poly C. Proc. of Sym. on Clinical Use of Interferon and Interferon Inducers. Zagreb, Yugoslavia, 1977, in press.